It's the opposite. A low-specs sport car is the easiest to tune. You can find extremely good suspension bundles (springs, adjustable dampers and ARB) for "quite cheap" (understand £500 a set if you stick with the stock suspension geometry), which can diabolically change the car's behavior. Also, you can buy a Clutch Pack LSD for around the same price.
I don't know yet about the wheel adjustment prices but I would say (correct me if I'm wrong) between £500 and £700 depending on what you want to do (toe, camber, or both). and let's say £400 for the aftermarket rims.
Thus, my setup on the XRG would cost around £2100, since I was too cheap to switch to supers (£400 more!)
On the other hand, more expensive cars are more expensive to tune.
In spec-car series, like the Mazda Spec in the US, the cars ned to have specific parts (such as the Mazdaspeed suspension) which is mandatory, but adjustable as you'd like to
In LFS, we are not driving completely stock road cars. Otherwise, most of them would have to have a fixed Open Diff. If it was the case, LFS would lose its title of "Racing Simulator" (as it simulates a bit the rules of Spec series) to the one of "Sunday Fast Driver Simulator".
The only thing that would be nice is, of course, the limitation of the transmission settings, but this belongs to another topic.
Concerning the rims, I thought the RS Watanabe were the lightest rims ever made? Did OZ beat them with their Super or Ultraleggera ?
Don't worry, I wasn't suggesting they were either I was just asking, because I need to find a pair of rims for my "rally" car and I plan on buying the lightest ones (when I got enough money ). So I wanted to have like the latest-to-date information about the wheels